U.S. officials say the U.S. has begun surveillance flights over Syria, after President Barack Obama gave the OK — in a move that could pave the way for airstrikes against Islamic State militants.

While the White House says Obama has not approved military action inside Syria, additional intelligence on the militants would likely be necessary before he could take that step. Pentagon officials have been drafting potential options for the president, including airstrikes.

One official said the administration has a need for reliable intelligence from Syria and called the flights an important avenue.

Two U.S. officials said Obama had approved the flights, while another U.S. official said early Tuesday that they had begun.

The officials were not authorized to discuss the matter by name and spoke on condition of anonymity.